Biological Evaluation of Proteins

Abstract

Various concepts of protein metabolism are reviewed, catabolism and anabolism, dynamic interaction between tissue constituents and diet, exogenous and endogenous metabolism, essentiality of amino acids, and digestibility. Total caloric intake is another factor that affects protein utilization. To determine nutritive value, N retained is measured as a function of growth, of N balance, or of repletion after depletion of protein stores (body protein, blood protein, liver protein, liver enzyme activity.) More rapid measurements of protein nutritional value by microbiological and chemical methods give results in fair agreement with the above.